The present invention concerns a cleaning tool for optical fiber connector, and more particularly a cleaning tool for optical fiber connector appropriate for the connector of small diameter optical fiber for branching.
FIG. 6 shows an example of optical fiber connector 63 for connecting mutually ends of two optical fibers 60, 60. Respective optical fiber 60 is protected by being inserted in the core of a hollow cylindrical ferrule 61 in a way to expose a tip thereof from the end face of this ferrule 61. Moreover, the optical fiber connector 63 is composed to provide a cylindrical housing 64 inside, and to insert a metal split sleeve 65 in this housing 64.
For connecting mutually ends of two optical fibers 60, 60 using the optical fiber connector 63, first, the end of the ferrule 61 of one optical fiber 60 is inserted in one end of the split sleeve 65 of the optical fiber connector 63, then the end of the ferrule 61 of the other optical fiber 60 is inserted in the other end, to make end faces of both optical fibers 60, 60 and ferrules 61,61 into mutual close contact.
In general, the end faces of optical fiber 60 and ferrule 61 are cleaned in advance before insertion in to the optical fiber connector 63; moreover, as shown in FIG. 6, when one optical fiber 60 and ferrule 61 are inserted in one end (left end in FIG. 6) of the split sleeve 65 and, in this state, the other optical fiber 60 and ferrule 61 are inserted in the other end (right end in FIG. 6) of the split sleeve 65, the right hollow portion of the split sleeve 65 is cleaned necessarily before the insertion, and the end faces of the optical fiber 60 and the ferrule 61 already inserted in the left side and the inner wall surface of the hollow portion of the split sleeve 65 should be cleaned out.
If such cleaning is not performed and oil or dust is deposited on the end face of the optical fiber 60 or the ferrule 61, light may not be transmitted after the connection, or gap generation may cause connection loss or reflection loss. Besides, because oil or dust deposited on the inner wall surface of the split sleeve 65 may shift the optical axis of both optical fibers and provoke connection loss.
Conventionally, as a means for cleaning the split sleeve inner wall surface of the optical fiber connector, or the end face of the optical fiber and the ferrule further inside thereof as mentioned above, a cleaning tool as described in the Japanese Utility Model Publication No. 2530291 has been proposed. This cleaning tool composed by attaching an elastic element to the tip on a supporting seem, and covering the outside of this elastic element with ultra fine fabric cleaning cloth, cleans up something by introducing a cleaning portion of this cleaning cloth into the split sleeve and turning or moving reciprocating back and forth. The structure provided with elastic element is alleged to allow an effective application of the cleaning cloth surface to the ferrule end face, so as to clean up surely.
Though this cleaning tool is effective for cleaning an optical fiber connector for artery optical fiber of which ferrule outer diameter is 2.5 mm, the diameter of the supporting stem should be reduced to 1 mm or less in order to be used for the cleaning of the optical fiber connector for branch optical fiber in which the ferrule outer diameter is half, i.e. 1.25 mm. As a consequence, the reduction of the root side diameter of the supporting stem pinched by fingers to afford rotation or reciprocating motion also causes to deteriorate its rigidity, and to flex easily during the cleaning operation; so it can not afford rotation or reciprocating motion to the cleaning cloth side and the cleaning can not be performed completely.
As a countermeasure thereof, it has been proposed a cleaning tool wherein only an elastic element made of urethane or the like is attached to the tip of the supporting stem in place of using a cleaning cloth of said cleaning tool, to increase the outer diameter of the stem by the cleaning cloth thickness. However, the lack of this cleaning cloth makes the cleaning effect of this cleaning tool insufficient, and moreover, the elastic element deterioration produces powder dust.
Another cleaning tool without cleaning cloth is also proposed wherein the supporting stem is made as straw like tube, this straw like tube is filled with fiber, which is exposed at the tip. However, this cleaning tool is not practical, because it cleans only the tip of the optical fiber and the ferrule and can not clean the inner wall surface of the split sleeve.
Therefore, the object of the present invention is to provide a cleaning tool for optical fiber connector that can clean effectively, even if it is designed for an optical fiber connector of reduced inner diameter.
To attain said object, the cleaning tool for optical fiber connector of the present invention is characterized by that a bar form stem and a support thinner than the bar form stem in thickness are molded with resin integrally in series in the longitudinal direction, and the outside of said support is covered with cleaning cloth made of ultra fine filament bundle presenting the filament fiber size of 0.1 denier or less.
Thus, as only the support to be covered with cleaning cloth is made thinner, while the root to be pinched with fingers to afford rotational or reciprocating motion is kept thick as bar form stem, flexion or bending will not occur easily during the cleaning operation including rotational or reciprocating motion, exhibiting an excellent cleaning effect.